Drill-tool.



G. H. GILMAN.

DHiLL TOOL.

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pn wm mw v. y 1g m G .wd

Patented Feb. 4, 1919.

more specifically referred to.

UNITED STATES PATENT OFFICE.

GEORGE H. GILMAN, OF CLAREMONT, NEW HAMPSHIRE, ASSIGNOR, BY MESNE ASSIGN` MENTS, T0 SULLIVAN MACHINERY COM PORATION OF MASSACHUSETTS.

PANY, 0F BOSTON, MASSACHUSETTS. .A COR- DRILL-TOOL.

Specification uf Letters Patent.

Patented Feb. 4, 1919.

To all 'whom it may Concern Be it `known that l, GEORGE H. GILMAN, a citizen oi' the United States, residing at Claremont, in the county of Sullivan, State of New Hampshire, have invented an Improvement in Drill-Tools, of which the fol lowing description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

My invention relates to rock drills, being more. particularly concerned with means for clearing the drill hole during cutting by means ot' water or pressure fluid or both.

My invention will be best understood by reference to the following description when taken in connection with the accompanying illustration of one specilic embodiment thereof, while its scope will be more particularly pointed out in the appended claims.

Figure 1 shows one form of pneumatic drill, partly in section, to which one embodiment of my invention is shown applied;

Fig. 2 is a detail of the cut-o` valve shown inthe tool of Fig. 1 for cutting off the connection between `the exhaust passages at opposite ends of the cylinder;

Fig. 3 is a detail in section showing a portion of the invention` relating to the holding chuck for the drill bit; and,

Fig. 4 is a section in detail showing a modified construction of the tool shown in Fig. 1.

Referring to the drawings and particularly to the embodiment of my invention there shown, Fig. 1 shows one form of the same applied to a constructionof hammer or impact drill tool, which is shown for illustrative purposes as of a usual and wellknown type, except for'features to be herein A It is to be understood that my invention is applicable to hammer ,drills-and tools of other c0nstructions'than the one herein shown, the particular .one illustrated being submitted for the sole purpose of disclosing one concrete embodiment of my present invention. Referring, however, to the details of the illustrated form of tool, the same is provided with a cylindrical or barrel portion 1, carrying at one end the grasping portion or handle 2, herein secured to the cylinder through the medium oif the intermediate valve block 3, the cylinder portion having at the opposite end the chuck 4 ixedly held within the end of the cylinder portion and acting as a holder for the shank 5 of the cutting tool or drill bit 6. IThe shank portion of the drill hit is provided with means, such as its hexagonal cross-section shape herein shown, to prevent relative ro` tative niormnent between the bit and the chuck, while permitting the slight necessary endwise movement between the two.

ln the specific type` ot' tool illustrated there is provided within the cylinder 1 the striking n'ieinilier l. having reoi-,procatory movement therein and adapted at each stroke to strike an impact receiving portion. herein (Fig. 1) the head end of the drill hit shank 5. As illustrated, this striking member is in the forni of a hammer piston, to the opposite ends of which the pressure fluid is alternately admitted and from which it is alternately exhausted, the control thereof residing in a differentially operated valve 8, as is common in this class of tools, although for purposes of the broad aspects of my invention the particular construction of the valve, or the presence or absence of a valve separate from the piston, is immaterial.

In the particular tool shown, pressure fluid is admitted to the hammer through the pressure supply pipe il connected to the base portion 10 of the handle, thence passing through suitable passages,(not herein necessary to show) to the valve chamber. The valve controls the admission of such pressure fluid to the head end 11 of the c 'linden whence' it is exhausted by passages (also not herein necessary to shoav) which communicate with one or more radial exhaust.`

passages 12, the latter connecting with the annular groove 13, from which the exhaust may he permitted to escape to the atmos-A phere through the adjustable valve 14.

Pressure Huid is admitted at the appropriate time to the lower end of the cylinder under control of the valve 8 through the admission passage 15, the exhaust being permitted to escape into an exhaust charnber 16 when the reduced end of the hammer piston withdraws on its upward stroke from the reduced portion 17 of the cylinder barrel which intervenes between the exhaust chamber and the cylnden The pressure fluid supply pipe 9 leads to a suitable source of compressed air or other pressure fluid, and there is also provided a supply pipe 18 leading to a suitable source, preferably of water, thc latter maintained under any desired or suitable head or ressure. The water supply may be controlled through any appropriate device, such as the controlling valve 19, and is connected to the elbow 20, the latter threaded into the walls of the cylinder and having free communication with the exh'aust chamber 16, so that a constant and easily controllable supply'of water may be admit ted to the exhaust chamber.

While any appropriate impact receivingl block or part may rest upon the end ot' the drill shank to receive the )low of the piston, in the present instance the shank of the drill hit itself extends into the exhaust chamber and constitutes such impact receiving part to receive the blow of the hammer piston and is provided with an axially arranged bore or passage 21 extending through the entire length of the drill bit, through which pas sage the combined exhaust pressure fluid and water is adapted freely to escape, thereby clearing lthe drill hole of chippings and dust.

To prevent. the possible leakage of water from the exhaust chamber 16, except through the central bore ofthe drill bit, any suitable means may be provided, but herein an effective device for vthis purpose is secured by the provision of the annular packing washerQQ of rubber or other suita le packing material interposed between the enlarged portion 23 of the drill bit and the mouth or face ot the chuck 4.

It will be observed that the elbow 20 provides a lixed water attachment for the cylinder which, if desired, may be taperlthreaded into the cylinder so that leakage is entirely avoided.

Although free access of the water to such space as 1s employed to receive the exhaust, may be prevented by the provision of a suitable means if desired, preferably, as in the illustrated embodiment of my invention, the water has free access to an exhaust space, such as the space 16, from which it is readily expelled through the longitudinal bit passage 21. The repeated discharge of the expanding pressure fluid to the exhaust space 16 recurs so rapidly that the chamber kept quite clear and the commingled air and water is caused to pass out of thas-space through thepassage 21 in a continuous stream, and as rapidly as it can enter the same, Without the least interference (as practice has demonstrated) with tl eflicient operation of the hammer piston.

Since exhaust occurs before completion of the up-piston stroke, the down stroke ofthe piston is receded by the expansive discharge of tlie exhaust pressure Huid from the forward end of the piston into the chamber '16. Such previous expansive discharge ol fluid, 'which fluid must escape through the longitudinal bil passage, positively prevents any possible tendency oll the water to fol lou' the pistou on its up stroke and impede the down-stroke thereof.

()ne advantage ol great practical importance consequent upon the employment oi a hammer drill constructed as shown, is the possibility ot' usingr the exhaust pressure fluid to assist in discharging the water while introducii'ig;l tluI latter longitudinally through the drill hit or other impact receiving parts without weakening the latter through the provision ot' a lateral supply passage or passages formed in the impact. receiving parts. LS'uch lateral introduction of the water also avoids trouble from the possible longitudinal displacement of the lsupposcdly alining passages in the impact receiving parts and the walls of the cylinder or other surroumlinzgr portion of the drill tool.

While l have described in connection with Fig. 1 the shank 5 of the bit as constituting the impact receiving part which projects into the exhaust space 16 to receive the blow of the piston and conduct the water therefrom, l recognize no distinction, so far as the broad aspects of my invention are concerned,

where separate and additional impact receivi ing members are employed to rest upon the end of the drill shank and communicate thereto the blow of the hammer piston.

In Fig. 4 I have shown the drill shank 5 surn'iounted by the impact receiving block 85, the same being provided with a longitudinal passage 24 alining with the drill bit passage 21 and opening communication between the same and the space beneath the hammer portion 7 of the piston. The drill shank being herein shown as of uniform cross-section, the block 35 will be normally pressed against the upper walls of the chamber 16, and there is provided means, such as a plurality of edge grooves in the block, permittin the free access of water from the chamber to the space above the impact block so as to permit its ready escape through the passa e 24, means, such as the packing ring 23x, Jeing also employed to prevent the passage of water down the sides of the block.

In the employment of the hammer drill described, the quantity of water passed through the drill bit maybe regulated as desired. If desired, the water supplv muy be entirely cut olf by means of the valve 19, or the water connections may be entirely removed from the tool, and the exhaust alone employed to clear the drill hole. In the event that the water supply is dispensed with, the exhaust from the lgwer end'of the piston ma be augment/ed` y leadlng also to the exhaust space 16 the exhaust pressure preferably fluid discharge from the opposite end of the cylinder through the radial passages 12.

For this purpose there is provided a passage 26 connecting the exhaust space 1G with the exhaust passages 1Q leading from the head'end of the cylinder. vWhere the tool is to be employed at times in connection with the Water supply referred to and at other times without the same, this passage is which may be employed to open or close at Will communication between the exhaust passa leading to the opposite ends of the cylin er, so that such communication may be' closed when the water supply is utilized and opened when such supply is cut ofi'. 1 have shown herein, for this purpose, a valve in the form of a transversely apertured plug 27 connected to an externally exposed head 28 by which the same may be placed in the position shown in Fig. 1, cutting ofi' communication between opposite ends of the passage 26, or in the position shown in Fig. 2, where such communication is opened. The plug 27 is slidably seated Within the threaded thimble 29 in the bottom of which it is normally seated by the spring 30. i pin 31 secured transversely through the stem of the plug is adapted to seat in either one of two sets of rightan le grooves formed in the head of the thim le. The plug may therefore be Withdrawn and turned to either of the positions shown, but when seated by its spring the pin 31 prevents its accidental displacement. Y

Where the exhaust discharge alone is employed, the plug valve 27 is arranged as shown in Fig. 2, permitting the exhaust from both ends of the cylinder to pass into the space 16 and through the drill bit passage 21. The escape cock 14 provides an auxiliary exhaust outlet to the atmosphere which may be more or less 'open or entirely closed, as conditions may require a lesser or greater discharge of the exhaust pressure fluid through the drill bit. If the tool is to be again used with the water supply described, the plug valve 27 may be set in the position shown in Fig. 1 and the exhaust cock 14 opened wide.

Referring to Figs. 1 and 3, the drill chuck 4 is preferably held fixed in position byr the pin or key 32 extending transversely through the surrounding cylinder portion and also through a groove or cutaway part of the bushing. In order to lock or retain this key in position1 the ends of the same are preferably held and protected by some means such, for example, as the encircling retaining ring 33, which is seated in an appropriately shaped groove in the outer walls of the surroundirg portion of the cylinder. Such retaining ring 1s preferably elastic and split, as at 34, so the same may be readily removed for the withdrawal of the pin when provided with suitable means' the removal of the bushing is `desired. This permits the bushing readily to be withdrawn without dismantling the tool, Whfle, on the other hand, no accidental displacement of the bushing is permitted.

Vv'hile I have referred to various advantages which are consequent upon; the use of the preferred construction of tool by which 1 have illustrated my invention.y and while other advantages will be obvious to those skilled in the art, my invention is not limited to the particular tool construction disclosed nor to such constructions as necessarily possess all the advantages of the one,` disclosed, but on the contrar comprehends extensive modifications and departures from the disclosed form thereof well as the utilization of the various features of novelty, as pointed out by the appended claims, severally `and each without reference to the absence or presence of the various other features of novelty residing in the said invention. i

1. A pressure fluid hammer drill having a hammer piston adapted to reciprocate therein, a drill bit presenting a suitable impact receiving part to receive the blow of the hammer, said drill bit having a longitudinal exit passage extending to the cutting end, said drill having an exhaustspace having open communication with the longitudinal passage in the bit, to which space the ressure fluid is intermittently exhausted rom the cylinder, and means also for admitting Water to the exhaust spare.

2. A pressure ifiuid hammer drill having a drill bit presenting an impact receiving part, a hammer piston to strike the same, said bit being provided with an open pas sage extending from the cutting end thereofI through the impact receiving part. said drill having a chamber communicating with the open end of the impact receiving;r part, and meansfor introducing pressure fluid exhaust and Water to said chamber for exit through said passage.

3. A hammer drill having a reciprocatory hammer piston, a drill bit provided with a longitudinal water passage leading to the cutting end, said bit presenting a suitable impart receiving part to the blow of the hammer piston, said halmmer drill being provided with a chamber in which the impact-receiving end of said part is exposed, which chamber comn'lunicates with the said longitudinal passage, and means for introducing water inte said chamber.

4. A pressure iiuid hammer drill having a hammer piston. a Vdrill bit provided with a longitudinal passage. leading to the cutting end, said drill having a chamber through which the hammer piston reciprocates, an

impact receiving portion exposed to the blow of said piston Within said chamber, means for supplying water to said chamber, and means also for supplying pressure fluid thereto.

5. A pressure Huid hammer drill having a hammer piston, a drill bit provided with `a longitudinal Water passage leading to the cutting edge, an impact-receiving part adapted to receive the hammer blow and communicate the same to the cutting edge of the tool, said drill being provided with a chamber within which the impact-receiving end of said art is exposed, said chamber communicating with said longitudinal drill bit passage, means for supplying Water to said chamber, and means lso for supplying pressure fluid exhaust tlriereto.

6. A pressure fluid hammer drill having a hammer piston, a drill bit, the latter having a longitudinal passage leading to its cutting edge, saidY drill having an exhaust chamber adapted to be intermittently placed in communication with one of" the cylinder ends, and means for supplying water to the drill bit passage by Way of the said exhaust chamber.

7. A hammer drill having a reciprocator hammer piston provided with a striking end, said drill havingr a chamber in which the striking end thereof operates and separated from the cylinder by a passage which said striking end renters land withdraws from, means for intermittently opening the same dirertly to the forward end 0f the cylinder to permit the escape of fluid pressure exhaust thereto, and a-drill bit having a combined pressure fluid and water exit passage leading to the cutting end, said passage having communication with the said chamber.

8. A hammer drill having a hammer piston provided with a striking end, said drill having a chamber within whleh the striking end is adapted to operate, said chamber being separate from the cylinder thereof, means for intermittently opening said chamber to the cylinder to permit the escape of pressure fluid exhaust thereto, means for supplying water to said chamber, a drill bit having a combined water and pressure fluid exhaust exit passage leading to the cutting end and communicating with said chamber, and means for supplying water through said Chamber to said passage.

l). A hammer drill having a hammer piston, a hollow drill bit, means for supplying water to said drill bit, and means for-causing pressure fluid exhaust to be supplied thereto during the backward stroke of the piston and during the first part of the forward stroke thereof.

10. A hammer drill having a hammer piston, a hollow drill bit, means t'or supplying water thereto, said drill having an exhaust space communicating with the hollow interior of said drill bit, and means for supplying pressure fluid exhaustv to the exhaust space during the backward movement of the piston.

11. A hammer drill having a reciprocatorv hammer piston, a hollow drill bit, said' f move, a drill bit having a longitudinal passage lead-ing to the cutting end thereof and having communication with said chamber, means for supplying water to said chamber, and means for causing the expulsion thereof through said passage with the assistance of exhaust pressure liuid fronrthe said hammer drill.

13. A hammer drill having a hammer piston and provided with a chamber in which the forward end of said hammer is adapted to move, a drill bit having a longitudinal passage leading to the cutting end thereof and provided at the opposite end with an impact-receiving part through which the said passage extends into the said chamber, means for admitting water to said chamber, and means for expelling the same through said passage by means of exhaust pressure fluid from the hevnmer drill.

14. A hammer drill having a hammer piston and provided with a chamber in-,whirh the forward end of' said piston. is adapted to move, a drill bit having a longitudinal passage leading to the cutting end thereof and having communication with said chamber, means for supplying water to said passage, and means for expelling the same through said passage by means of exhaust pressure fluid discharged from the forward end of the piston. l

15. A hammer drill having ton, and provided with an exhaust space to which exhaust pressure fluid is admitted on rearward movement of the piston. a drill bit having a longitudinal passage leading to thtI cutting end, and means for supplying water to said passage. there being provided communication between the supplied water and the exhaust space whereby the exhaust pressure fluid assists in expelling the water through said passage.

lli. A pressure fluid hammer drill having a hammer piston, a drill bit presenting a suitable impaet-rereiving part to the blow ol the piston. there being provided a longitudinal valveless passage extending through said drill bil and impart-receiving part from end to end, a chamber with which the inner end of said passage directly eommunirates, and means for expelling commingled presa hammer pissure uid and water through said chamber and passage. A

17. A hammer drill having a hammer p1st0n, a drill. bit, said bit having a Water passage leading to the cutting end thereof, means tor supplying water to said passage, and means for expelling the same therethrough through the assistance of the `ha1n mer pistons pressure fluid exhaust, said water supply having free access to the spare surrounding the striking end otI said piston.

18. In a pneumatic pereussive drill. a ovl.A inder, a piston, a hollow drill steel actuated hy said piston, passages for ronveying fluid from both ends of said rylinder to the hore of said steel. and means for throttling the exhaust of the drill.

19. The combination in a pneunuitie tool, of means for the passage et fluid from the rear of the Working piston directly lo the bore of a hollow drill or eu'tter carried by the tool tor the purpose of removing debris from the 'working fare, and means for throttliug the exhaust from the tool For the Control oi' the operation nl" the tool and of the {iow of tluid for the removal of the debris from the working fare', suhstantially as described.

20. A pneumatictool comprising a cylinder having ports for the admission and exhaust of lluid, a pistou within said rylimler, a hollow drill or rutter rarried h v the evliir der, means for the direet passage of fluid from the rear of the piston to the here of the hollow drill or cutter, means for the ront rol of the admission and exhaust ol' tluid lo and from the tore and rear ends of the piston, and means for throttling the exhaust Jfrom the tool substantially as deserilual.

2l.. A hammer drill having a` hammer pis ton from the opposite ends of vvhirh pressure fluid is alternately exhausted, a drill hit provided with a longitudinal discharge passage leading to the cutting end, and means for discharging the combined exhaust. from hoth ends of said piston through said drill bit.

22. A. hammer drill having a hammer piston from the opposite ends of whirh pressure l'luidis alternately exhausted, said drill having a passage leading to the atmosphere through which said pressure liuid exhaust may escape, a drill hit, the latter provided with an exit passage leading to the rutting end of said drill bit, and means also'permitting,r the esi-ape of the combined pressure fluid exhaust from both ends of said piston through said drill hit.

23. A hammer drill having a hammer piston from the opposite ends of which pressure liuid is alternately exhausted. a drill hit having an exit 'lissage leading to the eutting end thereo means permitting the escape of the combined exhaust pressure fluid from both ends of said piston through said passage, said drill having an auxiliary exhaust 'opening leading directly to the atmos pliere, and means for varying more or less the effective area of said auxiliary exhaust opening.

24. A hammer drill havin a hammer piston from the opposite ends o which pressure fluid is alternately exhausted, and means for Cutting off or establishing eonnnunieation at will between the exhaust passages leading to the opposite ends of said piston.

25. A drill tool having a Working cylinder, means for admitting pressure 4to and exhausting the same from the. the opposite ends of said cylinder alternately to causo the actuation of the tool. and means for cutting off 0r establishing communication 4at will between the exhaust passages leading to the opposite ends of said cylinder.

26. A rock drill having a working cylin der from the opposite ends of which pres sure {'luid is alternately exhausted, a drill bit having an interior passage, means for supplyin water to the cutting end of said drill iiit t irough the said passage.y means for Cutting ofi said water supply at will, means for supplying pressure Huid exhaust from one end of said eylinder through said passage, and means for opening or closing com* munieation between the exhaust passages leading to the opposite ends of' said (zylin-y der, said drill having an auxiliary exi aust passage leading to the atmosphere.

2'?. A hammer drill having` a reeipr0eatory hammer piston, a drill hit provided with loi/igitudinal water passage leading; to the cutting end, said hit preseutinpr a suitable in'ipact-reeeiving part to the lilou' ol the hammer piston, said hammer drill being provided with a chamber in which the imq pact-receiving end of said part is exposed, which chamber communicates 'with the said longitudinal passage, and means for introducing water into said chamber about the rear end of said impact-receiving portion.

28. A hammer drill having a hammer pis ton, a hollow drill-hit. means for supplying water to said drill-hit` and means under the Controlv ot said piston for Causing exhaust pressure .fiuid to he supplied thereto during the backward stroke of the piston.. and during the first part of the forward stroke thereof.

29. ln a drillingr machine, tlnl combination with a fiuid actuated motor and a drill oit assoeiated therewith, the latter having,r a passap way therein, of means for delivering exhaust Huid from one end of the motor to the drill hit, and means for preventing the passage of the actuating fluid from the other end of the motor to the drill bit and thereafter delivering the same as `exhaust fluid thereto.

30. In a drilling machine, the combinamay escape,

tion with a. fluid actuated motor and a drill bit associated therewith, the latter having a passageway therein, of means for delivermg exhaust fluid from one end of the motor to the drill bit, means for preventing the passage of the actuating fluid from the other end of the motor to the drill bit and thereafter delivering the same as exhaust fluid thereto, and means for controlling the flow of exhaust fluid to said bit.

31. A hammer drill having a hammer piston from the opposite ends of which pressure fluid is alternately exhausted, said drill having a passage leading to the atmosphere through which said pressure fluid exhaust a drill bit, the latter provided with an exit passage leading to the cutting end thereof, and means for controlling the supply of exhaust fluid either to the atmosphere or to the exit passage in said bit.

32. A hammer drill having a. hammer piston to the opposite ends of which pressure fluid is alternately supplied, said drill having a passage leading to the atmosphere, a `lrill blt, the latter provided with an exit passage leading to the cutting end thereof, and means for proportioning the flow of the pressure fluid through said passage leading to the atmosphere and through the passage in said bit to the cutting end thereof.

33. A hammer drill having a hammer piston from the, opposite ends of which pressure fluid is alternately exhausted, said drill having an exhaust assage leading to the atmosphere, a drill it, the latter provided with an exit passage leading to the cutting end thereof, and means for proportionin the flow of' the exhaust pressure fluid through said exhaust passage leading to the atmosphere and through said exit passage in said 34. A hammer drill having a hammer piston from the opposite ends of which pressure fluid is alternately exhausted, said drill having a passage leading-to the atmosphere through which said pressure fluid exhaust may escape, a drill hit, the latter provided with an exit passage leadin r to the cutting end thereof', and means including` a throttle valve for varying the proportion of the exhaust fluid flowing to the atmosphere and to said bit.

35. In a drilling machine, the combination with a fluid actuated motor and a drill bit associated therewith, the latter having a passageway therein, of means for delivering exhaust fluid through the motor to the dr1ll bit, means for preventing the pass: e of the actuating fluid from the motor [o the drill bit, and means other-than the first deliveringr means havin communication with the drill bit for suppying other cleansing fluid to the same in advance of said preventing mea-ns.

In testimony whereof, l have name to this specification, two subscribing witnesses.

GEO. H. GILMA N.

signed my 1n the presence of Witnesses:

E. J. BURCHARD, G. lV. BATEMAN. 

